1. Field of the Invention
This application relates to the field of computer aided design and more particularly to the field of computer modeling.
2. Description of Related Art
Computer-aided design software can be used to construct and manipulate computer drawings of objects referred to as “models”. The user is presented with a display of the model on the computer screen and manipulates the model using keyboard commands, a mouse/cursor combination, and other various input means. Changes to the model are reflected in the screen display of the model as the user makes the changes or, alternatively, in response to the user issuing a specific command to update the screen display of the model. In either case, the screen display of the model serves as the main source of model information to the user and as the user's reference for inputting and changing features of the model.
Although computer-aided design based on three-dimensional models has become increasingly prevalent, engineers and other designers continue to use conventional two-dimensional design drawings in many cases. Two-dimensional design drawings present a number of difficulties, one of which is that they are very difficult to read, even to experts. As two-dimensional renderings of different views of three-dimensional objects, the drawings necessarily separate relevant information about a unified object into a plurality of different views. This separation requires the user to understand the multiple views, rather than looking at the object as a whole. In addition, some views, such as section cuts, may not match any view that would actually be seen by a viewer of a real object, so that they require substantial imagination on the part of the user. As the complexity of a modeled object increases and as the number of views increases, it can be very difficult to keep track of the relationship of different views and of the relationship of different components within different views.
Despite these problems, two-dimensional drawings remain a standard modeling technique for a wide range of objects in many fields. Accordingly, a need exists for simplifying computer modeling of two-dimensional drawings.